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321.
Toyoda M Kugo H Shimizu T Takahashi D 《The Journal of the Acoustical Society of America》2008,123(2):825-831
Many studies on the sound transmission through a single plate have been carried out theoretically and experimentally. The transmission-loss characteristics, in general, follow mass law. Therefore, increasing mass of a plate is a fundamental measure to improve the insulation performance. This method, however, has limitations and might not be a reasonable alternative in current standards. Furthermore, the transmission loss at the critical frequency of coincidence is deteriorated significantly even if the mass is rather large. In this paper, the effect of the air-layer-subdivision technique is studied in detail from the viewpoint of the sound transmission problem of a single plate. An analytical model of an infinite single plate with a subdivided layer is considered and the improvement of the transmission loss is estimated. The limitations of the technique are clarified with some parametric studies. In order to validate the predictions, an experiment was carried out. The transmission loss of a glass board with the air layer subdivided by acryl partitions was measured in the experiment. They were in good agreement with the theoretical ones near and above the coincidence. 相似文献
322.
L. Jiang J. Li L. A. Nagahara N. Kino K. Kitazawa T. Iyoda K. Hashimoto A. Fujishima 《Applied Physics A: Materials Science & Processing》1995,61(1):17-21
C70 single crystals, free from solvent contamination, were grown via vapor phase transport technique. The (0001) face of the C70 crystal was imaged with Atomic Force Microscopy (AFM) under ambient atmosphere. Low-resolution images of a freshly prepared crystal revealed well-ordered faceted regions with multiple terraces extending over a region of several hundred square nanometers. The terraced structure in the images indicates that the crystals formed as a layer growth. In the high-resolution images, C70 molecules were resolved in a hexagonal close packed (hcp) structure with an average center-to-center distance of 10.5±0.5 Å. After one month's exposure to the ambient atmosphere, the molecules rearranged into a mixed structure consisting of hcp and face centered cubic (fcc) regions. 相似文献
323.
The Knight shift and the spin-lattice relaxation time of 7Li in lithium-ammonia solutions have been measured at -57°C over the concentration range XLi = 0.01–0.20 (XLi: mole fraction of Li). The Knight shift increases with increasing metal concentration, while the relaxation rate, 1/T1, shows a broad minimum around XLi = 0.07. 相似文献
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327.
Masumi Koishi Takafumi Ishizaka Takehisa Nakajima 《Applied biochemistry and biotechnology》1984,10(1-3):259-262
During the blending of two powders in a mixer, the preferential adhesion and sticking of fine powders onto other large powder
surfaces were usually observed. These frictional charging and physical adhesiveness properties can be used to modify and encapsulate
the surfaces of solids. In the present study, a centrifugal rotating-type mixer was used to study the possible wax encapsulation
process in binary (drug-potato starch) ordered powder mixes. The results indicate the expected trend of wax encapsulating
efficiency as the continuous and homogeneous adhesions of the fine drug particles on potato starch surfaces increases. The
wax encapsulated products offer a better controlled release property for drugs compared to that of the ordered drug-potato
starch mixture. 相似文献
328.
Matsuno K Katsufuji T Mori S Nohara M Machida A Moritomo Y Kato K Nishibori E Takata M Sakata M Kitazawa K Takagi H 《Physical review letters》2003,90(9):096404
The relationship between charge and spin degrees of freedom in a geometrically frustrated system, AlV2-xCrxO4 spinel, is investigated. Upon Cr doping, the charge-ordered phase of AlV2O4 is rapidly suppressed and a charge-disordered phase grows up instead. It is found that the magnetic ground state is a spin-glass state dominated by geometrical frustration for both phases, but larger spin entropy remains down to low temperatures in the charge-ordered phase, possibly owing to its two-dimensional character. 相似文献
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330.
Osa S Kido T Matsumoto N Re N Pochaba A Mrozinski J 《Journal of the American Chemical Society》2004,126(2):420-421
We report now the first single molecule magnet (SMM) consisting of d-f elements. The present study demonstrates that the synthesis of the d-f polynuclear molecule is a very promising approach to SMMs. (1) The d-f polynuclear molecule can be easily synthesized by the assembly reaction of the d-component and the f-component, (2) the high-spin ground state can be generated by a smaller number of metal ions than the d complex, and (3) the molecular magnetic anisotropy is easily derived from the f-component. 相似文献